CURLOPT_CERTINFO - request SSL certificate information
#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CERTINFO, long certinfo);
CURLOPT_CERTINFO(3) curl_easy_setopt options CURLOPT_CERTINFO(3)
NAME
CURLOPT_CERTINFO - request SSL certificate information
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CERTINFO, long certinfo);
DESCRIPTION
Pass a long set to 1 to enable libcurl's certificate chain info gath-
erer. With this enabled, libcurl will extract lots of information and
data about the certificates in the certificate chain used in the SSL
connection. This data may then be retrieved after a transfer using
curl_easy_getinfo(3) and its option CURLINFO_CERTINFO(3).
DEFAULT
0
PROTOCOLS
All TLS-based
EXAMPLE
curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "https://www.example.com/");
/* connect to any HTTPS site, trusted or not */
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
curl_easy_setopt(curl, CURLOPT_CERTINFO, 1L);
res = curl_easy_perform(curl);
if (!res) {
struct curl_certinfo *ci;
res = curl_easy_getinfo(curl, CURLINFO_CERTINFO, &ci);
if (!res) {
printf("%d certs!\n", ci->num_of_certs);
for(i = 0; i < ci->num_of_certs; i++) {
struct curl_slist *slist;
for(slist = ci->certinfo[i]; slist; slist = slist->next)
printf("%s\n", slist->data);
}
}
}
curl_easy_cleanup(curl);
}
AVAILABILITY
This option is supported by the OpenSSL, GnuTLS, Schannel, NSS, GSKit
and Secure Transport backends. Schannel support added in 7.50.0. Secure
Transport support added in 7.79.0.
RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
if not.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | web/curl |
+---------------+------------------+
|Stability | Uncommitted |
+---------------+------------------+
SEE ALSO
CURLOPT_CAINFO(3), CURLOPT_SSL_VERIFYPEER(3),
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from https://curl.se/down-
load/curl-7.83.1.tar.bz2.
Further information about this software can be found on the open source
community website at http://curl.haxx.se/.
libcurl 7.83.1 November 26, 2021 CURLOPT_CERTINFO(3)